There are many industrial processes that result in the production of sparks, either actively, passively or accidentally. Active production of sparks include those processes that generate a tremendous quantity of sparks, for example, welding and plasma cutting operations. Passive production of sparks refers to processes that are known to periodically generate sparks, yet spark production is relatively infrequent, for example a drying process that produces sparks primarily during startup and shutdown periods of operation. Accidental spark production refers to spark generation as the result of an accidental occurrence, for example, sparks are generated by the impact between two objects in an industrial process, and then the sparks become entrained in a process airstream. In many of these processes, the sparks are conveyed in a dust collection or air handling filtration system that treats the air surrounding the industrial process. The sparks are relatively small embers of burning substances discharged from a body in combustion. These sparks can cause damage to dust collection and filtration systems. For example, in a dust collection system, nuisance sparks carried downstream in a duct can burn through-holes in the filtration system's filter media, resulting in hazardous fires, or at a minimum, degradation in the filtration system's ability to effectively treat the air stream. Relatively large sparks are capable of also igniting combustible dust that may collect on the filter media, potentially causing catastrophic fires. Even without such fires, smaller sparks may burn-damage the filter media, requiring frequent replacement of the filter media, thereby significantly adding to the cost of operating and maintaining the filtration system.
Conventional spark detection and extinguishment systems for reducing the threat and incidence of fire are typically complex and may involve the application of a chemical retardant and/or water to the affected area upon detection of a spark(s). These conventional suppression systems are expensive, vulnerable to drift, tampering and malfunction. Additionally, activation of these systems often results in compromising the filtration system, because the system may need to be cleaned to remove the extinguishing substances and/or the byproducts of mixing and reacting of extinguishing substances with particulates in the process stream. Conventional extinguishment systems often use water deluge; these systems may be incompatible and potentially hazardous with particulate loading (i.e., some metal dusts) in certain industrial air streams. Also, filter media wetted in deluge systems may need to be removed and replaced with dry filter media, incurring significant maintenance costs and operational downtime.
Particularly for those industrial processes that take place on a smaller scale, incorporating known spark suppression systems is prohibitively expensive; therefore, there are few economically viable options available for smaller scale operations to have effective spark suppression capability.
Therefore, there is a need to provide a simple, economical and effective spark suppression system that may be easily and affordably installed in both large and small-scale industrial processes.